1 Introduction to AnatomyDr. Gary Mumaugh Bethel University

2 Overview of Anatomy and PhysiologyAnatomy – the study of the structure of body parts and their relationships to one another Gross or macroscopic Microscopic Physiology – the study of the function of the body’s structural machinery Pathology – the study of disease Pathophysiology – the study of disorders of function

3 Gross Anatomy Regional – all structures in one part of the body (such as the abdomen or leg) Systemic – gross anatomy of the body studied by system Surface – study of internal structures as they relate to the overlying skin

4 Microscopic Anatomy Cytology – study of the cellHistology – study of tissues

5 Other Branches of AnatomyDevelopmental anatomy Embryology Pathological anatomy (pathology) Radiographic anatomy Functional morphology

6 Levels of OrganizationCopyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Subatomic particles Atom Organ system Molecule Macromolecule Organ Organelle Organism Cell Tissue

7 Levels of Structural OrganizationChemical – atoms combined to form molecules Cellular – cells are made of molecules Tissue – consists of similar types of cells Organ – made up of different types of tissues Organ system – consists of different organs that work closely together Organism – made up of the organ systems

8 8

9 Levels of Structural OrganizationSmooth muscle cell Molecules Cellular level Cells are made up of molecules 2 Atoms 1 Chemical level Atoms combine to form molecules Smooth muscle tissue Heart 3 Tissue level Tissues consist of similar types of cells Cardiovascular system Blood vessels Epithelial tissue Smooth muscle tissue Blood vessel (organ) 6 Organismal level The human organism is made up of many organ systems Connective tissue 4 Organ level Organs are made up of different types of tissues 5 Organ system level Organ systems consist of different organs that work together closely

10 Functions of Life

11 Characteristics of LifeMovement – locomotion, propulsion (peristalsis), and contractility Responsiveness – ability to sense changes in the environment and respond to them Growth – increase in size of a body part or of the organism Reproduction – cellular and organism levels Cellular – an original cell divides and produces two identical daughter cells Organism – sperm and egg unite to make a whole new person

12 Respiration – O2 and CO2 exchangeDigestion – breakdown of ingested foodstuffs Absorption – passage of substances through membrane Assimilation – changing absorbed substances into different chemical forms Excretion – removal of wastes from the body Maintaining boundaries – the internal environment remains distinct from the external Cellular level – accomplished by plasma membranes Organism level – accomplished by the skin

13 Homeostasis Homeostasis is the ability to maintain a relatively stable internal environment in an ever-changing outside world The internal environment of the body is in a dynamic state of equilibrium Chemical, thermal, and neural factors interact to maintain homeostasis

14 Homeostatic Control MechanismsThe variable produces a change in the body The three interdependent components of control mechanisms are: Receptor – monitors the environments and responds to changes (stimuli) Control center – determines the set point at which the variable is maintained Effector – provides the means to respond to the stimulus

15 Variable (in homeostasis)Control center 3 Input: Information sent along afferent pathway to 4 Output: Information sent along efferent pathway to Effector Receptor (sensor) 2 Change detected by receptor 5 Response of effector feeds back to influence magnitude of stimulus and returns variable to homeostasis Stimulus: Produces change in variable 1 Imbalance Variable (in homeostasis) Imbalance

16 Negative Feedback In negative feedback systems, the output shuts off the original stimulus If the receptors measure deviations from a set point, effectors are activated to return things to normal Examples Thermostatic controls of body Regulation of blood glucose levels

17 Negative Feedback Figure 1.5

18 Positive Feedback In positive feedback systems, the output enhances or exaggerates the original stimulus Example: Regulation of blood clotting

19 Positive Feedback LoopsNormal way of producing rapid changes occurs with childbirth, blood clotting, protein digestion, fever, and generation of nerve signals 3 Brain stimulates pituitary gland to secrete oxytocin 4 Oxytocin stimulates uterine contractions and pushes fetus toward cervix 2 Nerve impulses from cervix Transmitted to brain 1 Head of fetus pushes against cervix

20 Homeostatic ImbalanceDisturbance of homeostasis or the body’s normal equilibrium Overwhelming of negative feedback mechanisms allowing destructive positive feedback mechanisms to take over Disease = Dis ease

21 Organ Systems of the BodyIntegumentary system Forms the external body covering Composed of the skin, sweat glands, oil glands, hair, and nails Protects deep tissues from injury and synthesizes vitamin D Skeletal system Composed of bone, cartilage, and ligaments Protects and supports body organs Provides the framework for muscles Site of blood cell formation Stores minerals

22 Muscular system Nervous system Composed of muscles and tendonsAllows manipulation of the environment, locomotion, and facial expression Maintains posture Produces heat Nervous system Composed of the brain, spinal column, and nerves Is the fast-acting control system of the body Responds to stimuli by activating muscles and glands

23 Cardiovascular systemComposed of the heart and blood vessels The heart pumps blood The blood vessels transport blood throughout the body Lymphatic system Composed of red bone marrow, thymus, spleen, lymph nodes, and lymphatic vessels Picks up fluid leaked from blood vessels and returns it to blood Disposes of debris in the lymphatic stream Houses white blood cells involved with immunity

24 Respiratory system Digestive systemComposed of the nasal cavity, pharynx, trachea, bronchi, and lungs Keeps blood supplied with oxygen and removes carbon dioxide Digestive system Composed of the oral cavity, esophagus, stomach, small intestine, large intestine, rectum, anus, and liver Breaks down food into absorbable units that enter the blood Eliminates indigestible foodstuffs as feces

25 Male reproductive systemUrinary system Composed of kidneys, ureters, urinary bladder, and urethra Eliminates nitrogenous wastes from the body Regulates water, electrolyte, and pH balance of the blood Male reproductive system Composed of prostate gland, penis, testes, scrotum, and ductus deferens Main function is the production of offspring Testes produce sperm and male sex hormones Ducts and glands deliver sperm to the female reproductive tract

26 Female reproductive systemComposed of mammary glands, ovaries, uterine tubes, uterus, and vagina Main function is the production of offspring Ovaries produce eggs and female sex hormones Remaining structures serve as sites for fertilization and development of the fetus Mammary glands produce milk to nourish the newborn

27 What systems do which function?Body covering Control - integration and coordination Transportation Absorption Excretion Reproduction

28 Anatomical Position Body erect, feet slightly apart, palms facing forward, thumbs point away from body

29 Directional Terms Superior and inferior – toward and away from the head, respectively Anterior and posterior – toward the front and back of the body Medial, lateral, and intermediate – toward the midline, away from the midline, and between a more medial and lateral structure

30 Directional Terms Proximal and distal – closer to and farther from the origin of the body Superficial and deep – toward and away from the body surface

31 Directional Terms

32 Directional Terms Table 1.1

33 Regional Terms: Anterior ViewAxial – head, neck, and trunk Appendicular – appendages or limbs Specific regional terminology

34 Regional Terms: Posterior View

35 Body Planes Sagittal – divides the body into right and left partsMidsagittal or medial – sagittal plane that lies on the midline Frontal or coronal – divides the body into anterior and posterior parts Transverse or horizontal (cross section) – divides the body into superior and inferior parts Oblique section – cuts made diagonally

36 Body Planes

37 Body Sections

38 Body Sections

39 Muscle segments (myotomes). Inner tube Dorsal hollow nerve tube Segmented outer tube Notochord Lung bud Pharyngeal pouches Spinal cord Notochord Muscle segments (myotomes) Brain Heart Digestive tube Human embryo; 5 weeks postconception 39

40 Muscle segments (muscles between ribs)Brain Pharynx Muscle segments (muscles between ribs) Spinal cord Heart Vertebrae Disc between vertebrae Digestive tube Inner tube Dorsal hollow nerve tube Segmented outer tube Notochord 40

41 Body Cavities Dorsal cavity protects the nervous system, and is divided into two subdivisions Cranial cavity is within the skull and encases the brain Vertebral cavity runs within the vertebral column and encases the spinal cord Ventral cavity houses the internal organs (viscera), and is divided into two subdivisions: thoracic and abdominopelvic

42 Body Planes

43 Body Planes

44 Body Cavities Thoracic cavity is subdivided into pleural cavities, the mediastinum, and the pericardial cavity Pleural cavities – each houses a lung Mediastinum – contains the pericardial cavity, and surrounds the remaining thoracic organs Pericardial cavity – encloses the heart

45 Body Cavities The abdominopelvic cavity is separated from the superior thoracic cavity by the dome-shaped diaphragm It is composed of two subdivisions Abdominal cavity – contains the stomach, intestines, spleen, liver, and other organs Pelvic cavity – lies within the pelvis and contains the bladder, reproductive organs, and rectum

46 Ventral Body Cavity Membranes

47 Ventral Body Cavity Membranes

48 Other Body Cavities Oral and digestive – mouth and cavities of the digestive organs Nasal –located within and posterior to the nose Orbital – house the eyes Middle ear – contain bones (ossicles) that transmit sound vibrations Synovial – joint cavities

49 Abdominopelvic RegionsUmbilical Epigastric Hypogastric Right and left iliac or inguinal Right and left lumbar Right and left hypochondriac

50 Organs of the Abdominopelvic Regions

51 Abdominopelvic QuadrantsRight upper Left upper Right lower Left lower

52 Microscopy—examining small structures through a microscopeMicroscopic Anatomy Microscopy—examining small structures through a microscope Light microscopy illuminates tissue with a beam of light (lower magnification) Electron microscopy uses beams of electrons (higher magnification)

53 Figure 1.9 Cells viewed by three types of microscopy.Cytoplasm Cell nuclei Extracellular material Light micrograph (190) Transmission electron micrograph (2250) Scanning electron micrograph, artificially colored (2500) 53

54 Preparing human tissue for microscopyMicroscopic Anatomy Preparing human tissue for microscopy Specimen is fixed (preserved) and sectioned Specimen is stained to distinguish anatomical structures Acidic stain—negatively charged dye molecules Basic stain—positively charged dye molecules

55 Scanning electron microscopyMicroscopic Anatomy Scanning electron microscopy Heavy metal salt stain—deflects electrons in the beam to different extents Artifacts Minor distortions of preserved tissues Not exactly like living tissues and organs

56 Clinical Anatomy—An Introduction to Medical Imaging TechniquesX ray—electromagnetic waves of very short length Best for visualizing bones and abnormal dense structures

57 Clavicles (collarbones)Figure X-ray images. Clavicles (collarbones) Ribs Air in lungs (black) Heart Diaphragm Radiograph of the chest Lower GI with barium contrast medium, normal 57

58 Advanced X-Ray TechniquesComputed (axial) tomography (CT or CAT) Takes successive X rays around a person’s full circumference Computer translates recorded information into a detailed picture of the body section

59 Right Left Liver Stomach Colon View Inferior vena cava Aorta SpleenLeft kidney Thoracic vertebra 59

60

61 Advanced X-Ray TechniquesAngiography Contrast medium highlights vessel structure Digital subtraction angiography (DSA) Images taken before and after contrast medium injection Computer subtracts “before” from “after” to identify blockage of arteries to heart wall and brain

62 Figure 1.12 Digital subtraction angiography (DSA).Narrowing of artery Artery supplying heart 62

63 Advanced X-Ray TechniquesPositron emission tomography (PET)— forms images by detecting radioactive isotopes injected into the body Sonography (ultrasound imaging)—body is probed with pulses of high-frequency sound waves that echo off the body’s tissues Imaging technique used to determine the age of a developing fetus

64 Figure 1.13 Positron Emission Tomography (PET).Brain Heart Liver Kidney Colon Urinary bladder PET scan before treatment. Tumors visible in right breast and in liver PET scan after treatment 64

65 Figure 1.14 Ultrasound image of a fetus in the uterus.Head Body 65

66 Baby Loves Doritos

67 Advanced X-Ray TechniquesMagnetic resonance imaging (MRI)— produces high-quality images of soft tissues Distinguishes body tissues based on relative water content

68 Figure 1.15 Magnetic resonance image (MRI).Normal knee, meniscus intact Injured knee, torn meniscus MRI of knee, sagittal section. Arrow indicates meniscus. Note tear in meniscus in bottom image. Volume rendering of an MRI of the head 68